Medical instruments with an integrated optical fiber and methods of manufacture

ABSTRACT

An illuminated microsurgical instrument comprises a distally projecting tubular member arranged to perform a medical procedure at an interventional site, a sheath member surrounding a portion of the tubular member, and an optical fiber extending along a length of the outer surface of the tubular member between the tubular member and the sheath member. A method of manufacturing an illuminated microsurgical instrument comprises placing an optical fiber on a positioning member, placing a sheath member around the optical fiber and positioning member and securing the sheath member to the optical fiber, removing material from a distal end of the sheath member and optical fiber at a non-perpendicular angle with respect to a longitudinal axis of the positioning member, removing the positioning member from within the sheath member, and placing the sheath member with the optical fiber secured thereto around a distally projecting tubular member.

PRIORITY CLAIM

This application claims the benefit of priority of U.S. ProvisionalPatent Application Ser. No. 62/642,734 titled “Medical Instruments withan Integrated Optical Fiber and Methods of Manufacture,” filed on Mar.14, 2018, whose inventor is Chenguang Diao, which is hereby incorporatedby reference in its entirety as though fully and completely set forthherein.

TECHNICAL FIELD

The present disclosure is directed to systems and instruments for use inmedical procedures, and associated methods of manufacture, and moreparticularly, to methods and systems involving a need for an opticalfiber to be inserted within a body cavity.

BACKGROUND

Medical procedures are often performed within significantly limitedconfines of a particular body structure or cavity, such as within theposterior chamber of the human eye. For example, vitreo-retinalprocedures are commonly performed to treat many serious conditions ofthe posterior segment of the eye. In particular, vitreo-retinalprocedures may treat conditions such as age-related macular degeneration(AMD), diabetic retinopathy and diabetic vitreous hemorrhage, macularhole, retinal detachment, epiretinal membrane, cytomegalovirus (CMV)retinitis, and many other ophthalmic conditions.

A surgeon performs vitreo-retinal procedures with a microscope andspecial lenses designed to provide a clear image of the posteriorsegment. Several tiny incisions just a millimeter (mm) or so in diameterare made on the sclera at the pars plana. The surgeon insertsmicrosurgical instruments through the incisions, such as a light sourceto illuminate inside the eye, an infusion line to maintain the eye'sshape during surgery, and other instruments to cut and remove thevitreous body. A separate incision may be provided for eachmicrosurgical instrument when using multiple instruments simultaneously.

During such procedures, proper illumination of the inside of the eye isimportant. Typically, an optical fiber is inserted into one of theincisions in the eye to provide the illumination. A light source, suchas a halogen tungsten lamp or high pressure arc lamp (metal-halides,Xenon), may be used to produce the light carried by the optical fiberinto the eye. The light passes through several optical elements(typically lenses, mirrors, and attenuators) and is transmitted to theoptical fiber that carries the light into the eye.

In such procedures, incisions are typically only made large enough toaccommodate the size of the microsurgical instrument being inserted intothe interior of the eye. Efforts to minimize the incision size generallyinvolve reducing the size of the microsurgical instrument. However, areduction in size can result in a reduction in instrument strength orrigidity. Depending on the size of the microsurgical instrumentemployed, the incision may be small enough to render a resulting woundsubstantially self-healing, thereby eliminating the need to employadditional procedures to close the incision, such as sutures. Also,reducing the number of incisions may be accomplished by integratingvarious microsurgical instruments. For example, the optical fiber may beincorporated into the working end of a microsurgical instrument.Unfortunately, at least some prior attempts at integrating opticalfibers with microsurgical instruments have resulted in a decrease inilluminating efficiency or in other visualization problems thatotherwise adversely effected the distribution of light emitted from theoptical fibers.

SUMMARY

The present disclosure is directed to exemplary illuminatedmicrosurgical instruments and methods of manufacturing illuminatedmicrosurgical instruments.

In some examples, an illuminated microsurgical instrument comprises adistally projecting tubular member arranged to perform a medicalprocedure at an interventional site, the tubular member having alongitudinal axis, a distal tip and an outer surface; a sheath membersurrounding a portion of the tubular member and extending toward thedistal tip of the tubular member; and an optical fiber extending along alength of the outer surface of the tubular member between the tubularmember and the sheath member, wherein a distal tip of the optical fiberis directed toward the distal tip of the tubular member. A distal end ofthe sheath member may comprise an angled end surface that lies in aplane at a non-perpendicular angle with respect to the longitudinal axisof the tubular member. The distal tip of the optical fiber may comprisean angled face that lies in substantially the same plane as the angledend surface of the sheath member.

The optical fiber may be fixed in position at least in part relative tothe sheath member. A distal edge of the sheath member may be disposed ata location closer to the distal tip of the tubular member than theoptical fiber, such that the optical fiber is recessed from the distaledge of the sheath member.

The angled face of the distal tip of the optical fiber may be angledtoward the outer surface of the tubular member and may cause a field ofillumination to be directed substantially away from the outer surface ofthe tubular member.

In some examples, a method of manufacturing an illuminated microsurgicalinstrument comprises placing an optical fiber on a positioning member;placing a sheath member around the optical fiber and positioning memberand securing the sheath member to the optical fiber to form a sheathmember and optical fiber assembly; removing material from a distal endof the sheath member and optical fiber assembly such that an end surfaceof the sheath member and optical fiber assembly is angled at anon-perpendicular angle with respect to a longitudinal axis of thepositioning member; removing the positioning member from within thesheath member, with the sheath member remaining secured to the opticalfiber; and placing the sheath member with the optical fiber securedthereto around a distally projecting tubular member.

The positioning member may comprise a material to prevent adhesionbetween the positioning member and the optical fiber, such aspolytetrafluoroethylene. Alternatively, the positioning member maycomprise a meltable material that melts at a lower temperature than thesheath member and optical fiber, such as a wax.

Removing material from a distal end of the sheath member and opticalfiber assembly may comprise angle polishing the sheath member andoptical fiber assembly.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory innature and are intended to provide an understanding of the presentdisclosure without limiting the scope of the present disclosure. In thatregard, additional aspects, features, and advantages of the presentdisclosure will be apparent to one skilled in the art from theaccompanying drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate implementations of the devices andmethods disclosed herein and, together with the description, serve toexplain the principles of the present disclosure.

FIG. 1 illustrates a perspective view of an exemplary surgical system,according to an implementation consistent with the principles of thepresent disclosure.

FIG. 2 is an illustration of an exemplary block diagram of the surgicalsystem of FIG. 1, according to an aspect consistent with the principlesof the present disclosure.

FIG. 3 is a cross-sectional illustration of an exemplary surgicalinstrument, according to aspects of the present disclosure.

FIG. 4A is a perspective view of the surgical instrument of FIG. 3,according to aspects of the present disclosure.

FIG. 4B is a detailed perspective view of a portion of the distal end ofthe surgical instrument included in FIG. 4A, according to aspects of thepresent disclosure.

FIG. 5A is a cross-sectional illustration of the distal end of theexemplary surgical instrument in FIG. 3, according to aspects of thepresent disclosure.

FIG. 5B is an end view of the distal end of the exemplary surgicalinstrument of FIG. 5A showing an illumination pattern thereof, accordingto aspects of the present disclosure.

FIG. 5C is a detailed view of a distal end of an optical fiber that maybe included in the exemplary surgical instrument of FIG. 5A, accordingto aspects of the present disclosure.

FIGS. 6A and 6B are detailed perspective views of the distal ends ofexemplary surgical instruments, according to aspects of the presentdisclosure.

FIGS. 7A, 7B, and 7C depict cross-sectional views of an optical fiberthat may be included in exemplary surgical instruments, according toaspects of the present disclosure.

FIG. 8 is a perspective view of an alternative sheath member, accordingto aspects of the present disclosure.

FIGS. 9A and 9B are detailed perspective views of the distal ends ofexemplary surgical instruments including the sheath member of FIG. 8,according to aspects of the present disclosure.

FIG. 10 is a cross-sectional illustration of the distal end of anotherexemplary surgical instrument similar to that shown in FIG. 5A,according to aspects of the present disclosure.

FIGS. 11A-11E illustrate a method of manufacturing the exemplarysurgical instrument illustrated in FIG. 10.

The accompanying drawings may be better understood by reference to thefollowing detailed description.

DETAILED DESCRIPTION

The present disclosure contains subject matter that is related to thesubject matter disclosed in U.S. Provisional Patent Application No.62/423,499, filed Nov. 17, 2016 (entitled “Medical Instrument with anIntegrated Optical Fiber”), U.S. Provisional Patent Application No.62/543,548 filed Aug. 10, 2017 (entitled “Medical Instrument with anIntegrated Optical Fiber”), U.S. Non-Provisional patent application Ser.No. 15/805,519 filed Nov. 7, 2017 (entitled “Medical Instrument with anIntegrated Optical Fiber”) and U.S. Non-Provisional patent applicationSer. No. 15/814,929 filed Nov. 16, 2017 (entitled “Medical Instrumentwith an Integrated Optical Fiber”), the disclosures of which are herebyincorporated by reference in their entirety as though fully andcompletely set forth herein.

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the implementationsillustrated in the drawings, and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of the disclosure is intended. Any alterations and furthermodifications to the described devices, instruments, methods, and anyfurther application of the principles of the present disclosure arefully contemplated as would normally occur to one skilled in the art towhich the disclosure relates. In particular, it is fully contemplatedthat the features, components, and/or steps described with respect toone implementation may be combined with the features, components, and/orsteps described with respect to other implementations of the presentdisclosure. For simplicity, in some instances the same reference numbersare used throughout the drawings to refer to the same or like parts.

The present disclosure is broadly directed to systems and instrumentsfor providing an optical fiber within a body cavity during an operationperformed therein without requiring a separate incision to be made. Moreparticularly, some aspects of the present disclosure are directed tosystems and instruments for providing for illumination through anoptical fiber positioned within the body cavity. In some examples, theillumination is provided through an optical fiber extending along alength of another surgical instrument or tool within the body cavity.For example, a vitrectomy procedure may be performed to remove vitreousfrom the eye of a patient using a vitrectomy probe introduced into theeye to position a vitrectomy needle at an interventional site. Ratherthan form two incisions in the eye of the patient, the optical fiber maybe positioned along a portion of the vitrectomy needle. The opticalfiber may have a distal tip through which light is introduced or emittedinto the posterior chamber of the eye, when the distal tip of thevitrectomy probe is positioned within the eye. The removal of thevitreous may be of particular importance, because residual vitreous cancause post-operative retinal tearing, retinal detachment, etc.

The clear vitreous may be visualized due to light scattering off thevitreous fibers contained within it. The lighting may be directedproximate the cutting portion of the vitrectomy probe in order to bettervisualize the vitreous being cut. Depending on the implementation, theoptical fiber may be secured at least partially to a vitrectomy needleby a sheath that also protects the optical fiber. Thus, implementationsof the present disclosure provide for improved illumination forinner-cavity procedures, such as vitrectomy procedures, while minimizingthe number of incisions required to be made to permit entry to thecavity. The illumination provided by implementations of the presentdisclosure may result in high irradiance at the surgical site, e.g., atthe port of the vitrectomy needle. This may provide for a high signal tonoise ratio or contrast to facilitate visualization of the fibers in thevitreous. While specific examples of implementations are provided hereinthat are directed to vitrectomy procedures and devices, the principlesof the present disclosure extend beyond vitrectomy instruments andprocedures.

FIG. 1 illustrates a surgical system 100, according to an exemplaryimplementation. The surgical system 100 includes a base housing orconsole 102 and an associated display screen 104. In the implementationsof the surgical system 100 that are directed to vitrectomy procedures,the display screen 104 may show data relating to system operation andperformance during such vitrectomy surgical procedures. In animplementation, the console 102 may be mobile, for example includingcasters or wheels 105 to facilitate movement as necessary. In analternative implementation, the console 102 may not include wheels 105.

The console 102 may be referred to as a “base housing” and may include aplurality of subsystems that cooperate to enable a surgeon to perform avariety of medical procedures, such as ophthalmic surgical procedures. Amicrosurgical, or simply “surgical,” instrument 110, which may beimplemented as a handpiece, may attach to the console 102 and may form apart of the surgical system 100. The surgical instrument 110 may be avitrectomy probe, in some implementations. Additionally, someimplementations of the instrument 110 may include non-surgical medicalinstruments, such as diagnostic instruments, imaging instruments, ortherapeutic instruments. As illustrated in FIG. 1, the surgicalinstrument 110 is an illuminated vitrectomy probe that may form part ofa vitrectomy subsystem as described herein. The vitrectomy probe mayinclude an outer vitrectomy needle and an inner reciprocating cutter.

The surgical instrument 110 may be coupled to the console 102 by one ormore conduits. In the depicted implementation, the surgical instrument110 is coupled to the console 102 by a first conduit 106 and a secondconduit 108. The conduits 106 and 108 may provide the surgicalinstrument 110 with access to multiple subsystems of the console 102.For example, the first conduit 106 may contain an optical fiber coupledto or forming part of a fiber subsystem within the console 102, whilethe second conduit 108 may couple the surgical instrument 110 to or mayform a part of a fluidics subsystem.

To facilitate operator control of the surgical system 100, the surgicalinstrument 110 itself may include one or more control elements, such asbuttons or dials. Additionally, a footpedal 109 may include controlelements that can be activated, deactivated, or varied by the operator'sfoot. Moreover, the display screen 104 may be a touchscreen havingcontrols displayed thereon that can be manually activated by theoperator. Other mechanisms such as voice control, a keyboard, a mouse,etc., may be provided in various implementations of the surgical system100 to facilitate control of various subsystems, such as a fibersubsystem to facilitate visualization, diagnosis, or treatment at adistal region of the surgical instrument 110.

FIG. 2 is a block diagram of the surgical system 100 including theconsole 102 and several relating subsystems thereof. As illustrated,console 102 includes a computer subsystem 103, the display screen 104(FIG. 1), and a number of subsystems that are used together to performocular surgical procedures, such as emulsification or vitrectomysurgical procedures, for example. The computer subsystem 103 may includeone or more processing devices, such as a central processing unit orcentral processor, and an information or data storage system. The datastorage system may include one or more types of memory, such as RAM(Random-access memory), ROM (read-only memory), flash memory, adisk-based hard drive, and/or a solid-state hard drive. The processingdevices and storage system may communicate over a bus, which may alsopermit communication with and between one or more of the plurality ofsubsystems of the surgical system 100.

The subsystems in the exemplary implementation of FIG. 2 may include afootpedal subsystem 130, for example, for facilitating control via thefootpedal 109 of FIG. 1. The depicted surgical system 100 furtherincludes a fluidics subsystem 140, which may include an aspirationvacuum 142 and an irrigation pump 144 that connect to a fluid conduit146. The surgical system 100 includes a handpiece subsystem 112 tofacilitate operation and control of the surgical instrument 110. Forexample, the handpiece subsystem 112 may receive control signals fromthe surgical instrument 110 to turn on or off an illumination sourcecoupled to the surgical instrument 110.

Implementations of an included fiber subsystem 120 may provide anillumination source. Other implementations of the fiber subsystem 120may provide laser light for ablation, may be used in imaging through theoptical fiber, or other functions. The fiber subsystem 120, which may bean illumination subsystem, may be coupled to the surgical instrument 110by an optical fiber, extending within one of the first and secondconduits 106 and 108. The fiber subsystem 120 may include or be referredto as an illumination source or light source, although the source may beone component of several components of the fiber subsystem 120.Implementations of the fiber subsystem 120 may further include sensors,lenses, filters, and other optical devices.

The surgical system 100 further includes a control subsystem 150including a communication module 152. The control subsystem 150 mayfacilitate communication between the subsystems included in the surgicalsystem 100. For example, an operator may provide an input via thefootpedal 109. The input may be interpreted or encoded by the footpedalsubsystem 130 as a control signal to vary, for example, an intensity ofillumination provided to the surgical instrument 110. The footpedalsubsystem 130 may communicate the control signal to the controlsubsystem 150, which may interact with a fiber subsystem 120 to alter acharacteristic of illumination provided by the subsystem 120 or to turnthe illumination on or off. In some implementations, the surgicalinstrument 110 may, additionally or alternatively, be used to controlillumination status or intensity. For example, the surgical instrument110 may include a dimmer switch or other control mechanism to receiveinput from an operator to adjust the illumination.

These subsystems and others may be included additionally oralternatively in other implementations. To optimize performance of thedifferent subsystems during surgery, the operating parameters differaccording to, for example, the particular procedure being performed, thedifferent stages of the procedure, the surgeon's personal preferences,whether the procedure is being performed in the anterior or posteriorportion of the patient's eye, and so on.

The different subsystems in the console 102 comprise control circuitsfor the operation and control of the respective microsurgicalinstruments or instrument components. The computer subsystem 103 and thecontrol subsystem 150 may govern and dynamically redefine theinteractions and relationships between the different subsystems toproperly perform an ocular surgical procedure and to properlycommunicate information to the operator of the surgical system 100through the display 104 and/or through a coupled microscope or wearablecomputing device.

As shown in FIG. 2, the surgical instrument 110 may be coupled tovarious subsystems within the surgical system 100. As depicted, thesurgical instrument 110 is connected to the handpiece subsystem 112, thefiber subsystem 120, and the fluidic subsystem 140 via the conduits 106and/or 108 as shown in FIG. 1.

Using the input devices, a surgeon, scientist, or other user may selector adjust parameters that affect the relationships between the differentsubsystems of the console 102 and that affect the performance of thesurgical instrument 110 and/or additional instruments connected to theconsole 102. For example, a surgeon may increase or decrease anintensity of light provided by the fiber subsystem 120. Additionally, asurgeon may change one or more parameters for the operation of thesurgical instrument 110, such as an aspiration/suction parameter or anoscillation parameter of the vitreous cutting mechanism included in thesurgical instrument 110. Accordingly, based on a user input, a user maychange or adjust the relationships from those that were coded into theconsole by the system programmers.

Because the surgical instrument 110 is configured to receive light fromthe fiber subsystem 120, the surgeon may be able to visualize aspects ofthe surgical operations performed by or near by the distal tip of thesurgical instrument 110, without requiring multiple incisions andwithout requiring the manipulation and handling of two or more separatedevices within the small confines of the eye or in another cavity orarea of the patient.

FIG. 3 shows a partial cross-sectional illustration of an exemplaryvitrectomy probe 300 that may correspond to the surgical instrument 110shown in FIGS. 1 and 2. In this example, the probe 300 may be apneumatically-driven vitrectomy probe configured to be held in the handof a surgeon during use. The probe 300 includes a handpiece housing 301having a proximal end 302 and a distal end 310. Some implementations ofthe probe 300 operate by receiving pneumatic pressure via the secondconduit 108 of FIG. 1, which may be coupled to a protruding coupler 304at the proximal end 302. The coupler 304 may attach the proximal end 302of the probe 300 to the second conduit 108 by a barb, an adhesive, orother coupling means. The proximal end 302 further includes anadditional coupler 306 that is configured to receive or couple to thefirst conduit 106 of FIG. 1.

In this implementation, the second conduit 108 provides an activationenergy source to provide an oscillation energy to components of theprobe 300. As illustrated, a pneumatic source may form a part of thefluidics subsystem 140 of FIG. 2 and may be coupled to an oscillationmotor, shown here as a diaphragm 308. In some embodiments, theoscillation motion may be provided by an oscillating electric motor orother non-pneumatic activation means. Further, the conduit 108 may becoupled to an aspiration source to enable aspiration of material throughthe probe 300. By causing the diaphragm 308 to oscillate, a drive member309 may also be caused to vibrate or oscillate. The drive member 309 mayextend between the proximal end 302 and the distal end 310. The drivemember 309 may be an elongate tubular member having a lumen extendingtherethrough such that material may be aspirated to the console 102 ormaterial may be pumped through the drive member 309 to the distal end310 of the probe 300.

As depicted in FIG. 3, the distal end 310 of the handpiece housing 301includes or supports a collar structure 312 that provides a degree ofrigidity and support to a vitrectomy needle 320. The vitrectomy needle320 may include inner and outer components that may be used for cuttingvitreous proximate a distal tip 322 of needle 320 during vitrectomyprocedures as is described herein and in further detail.

The handpiece housing 301 includes a chamber 330 that extends from theproximal end 302 to the distal end 310. The chamber 330 may be referredto herein as an optical fiber slack chamber 330. A length of an opticalfiber 332 extends within the slack chamber 330. For example, the opticalfiber 332 may extend from the fiber subsystem 120, through the firstconduit 106, through the optical fiber slack chamber 330, through thecollar structure 312, and along the vitrectomy needle 320. The fiber mayterminate anywhere along the needle 320, such as at or near the distaltip 322 thereof or closer to the distal end 310 of the handpiece housing301. The optical fiber 332 may be affixed to the needle 320 at a distalregion of the fiber 332, which may provide a proximal region of theneedle over which the optical fiber 332 is permitted to axially displaceindependently of the needle 320, in some implementations. In some otherimplementations (e.g., as seen in FIGS. 4A-6B), the optical fiber 332may be affixed to the sheath 340. When the needle 320 flexes during usein a medical procedure, the portion of the fiber 332 extending along theneedle 320 may relatively, axially displace according to the directionof bending of the needle 320. To prevent strain on the optical fiber332, the collar structure 312 may include one or more passages withguiding surfaces to permit independent elongate displacement of theoptical fiber 332 along a proximal region of the needle 320 within thespace between the tubular member 342 and sheath 340, and to permitslideable transition of the optical fiber 332 through a straight, offsetor curved path between the needle 320 and the slack chamber 330. Theslack chamber 330 may include sufficient space to accommodate slackoptical fiber in one or more fiber bends 334. The fiber bends 334 mayhave a radius of curvature sufficiently large to avoid affecting theillumination passing through the optical fiber 332, while stillproviding for an amount of slack fiber to be contained within theoptical fiber slack chamber 330. The optical fiber 332 may have aportion fixed within the proximal portion of the slack chamber 330 orthe distal end of the handpiece housing 301. Accordingly, the amount ofslack fiber may accommodate flexing of the vitrectomy needle 320. Someimplementations of the probe 300 may include an optical fiber slackchamber in the coupled conduit 106 in addition to or as an alternativeto the slack chamber 330 included in the handpiece housing 301.

FIGS. 4A and 4B provide perspective views of the probe 300 of FIG. 3.Both of these figures depict an implementation of the needle 320. Asshown in FIG. 4A, the needle 320 includes a sheath 340 extending alongan outer surface of an elongate tubular member 342. The elongate tubularmember 342 extends beyond a distal edge 349 (shown in more detail inFIG. 5A) of the sheath 340. The distal tip 322 may be the distal tip ofthe elongate tubular member 342. FIG. 4B is a more detailed view of theneedle 320 depicted in FIG. 4A. FIG. 4B further illustrates that theelongate tubular member 342 can include an opening or port 346, intowhich vitreous may be aspirated and cut during a vitrectomy procedure.FIG. 4B also depicts an opening 348 in the sheath 340. The opening 348may provide a window through which a liquid or gel sealant material maybe introduced to seal off any small gaps that are present between theinner surface of the sheath 340 and the outer surface of the elongatetubular member 342. In some implementations, multiple openings may beprovided in the sheath 340 to provide for the introduction of a sealant.The opening 348 may also be provided in or proximate to the collarstructure 312 at the distal end 310 of the housing 301. In someimplementations, the sealant is a gel that can be injected through theopening 348. The gel may be cured after injection to further ensure aproper seal between the sheath 340 and the elongate tubular member 342.Affixing the optical fiber 332 to the sheath 340 may result in passivealignment of the optical fiber 332 relative to the sheath 340. Thepassive alignment may minimize glare and reduce the assembly cost.

In some implementations, a 360-degree seal may be used between the innersurface of the sheath 340 and the outer surface of the elongate tubularmember 342 in order to inhibit potential passage for backflow in thearea between the sheath 340 and the tubular member 342. Thus, the liquidor gel sealant material introduced through the opening(s) 348 may extendcompletely or nearly completely around the circumference of the tubularmember 342 to form a seal that extends 360-degrees or nearly 360-degreesaround the tubular member 342 between the sheath 340 and tubular member342. In some implementations, the area between the sheath 340 andtubular member 342 may be partially or fully blocked in other ways, suchas by one or more parts, welding, sealant, or any combination thereof.

If the space or gap between the inner surface of the sheath 340 and theouter surface of the elongate tubular member 342 is not adequatelyclosed off or sealed, a possibility exists for a potential passage forbackflow in the area between the sheath 340 and the tubular member 342.In a vitreo-retinal procedure, the distal end of the surgical instrumentmay be placed inside the posterior chamber of the eye, while theproximal end remains outside the patient. Due to the intraocularpressure being higher than atmospheric pressure, there may be a higherpressure at the distal end of the instrument than at the proximal end.If a passage exists in the space or gap between the inner surface of thesheath 340 and the outer surface of the elongate tubular member 342,there is a potential for passive flow of vitreous in that passage due tothe higher pressure in the eye as compared to atmospheric pressure. Thiscould lead to traction of the retina or other complications.Accordingly, in some implementations, the area between the sheath 340and tubular member 342 is partially or wholly closed off as describedabove, for example by sealant.

FIG. 5A shows therein a cross-sectional view of the distal region of thevitrectomy needle 320 of FIGS. 3A-C. The sheath 340 surrounds theelongate tubular member 342 and an inner tubular member 343, which is anelongate tubular member extending within a lumen 347 of the elongatetubular member 342. The distal edges 339 of the inner tubular member 343may be sharpened or include a shape to facilitate cutting of vitreous asthe inner tubular member 343 oscillates back and forth within the lumen347 and cycles past the port 346. Vitreous aspirated into the port 346may be cut by the oscillating inner tubular member 343.

The sheath 340 further surrounds and encloses the optical fiber 332. Adistal edge 349 of the sheath 340 may be offset from a center of theport 346 by a distance D1. The distance D1 may range from about 2 mm toabout 3 mm in some implementations. Other implementations may have adistance D1 that is greater or lesser than this range. The optical fiber332 includes a face 352 at the distal end thereof. Illumination in anillumination beam 354 may be emitted from the face 352 to illuminate anarea proximate the port 346. For example, during a vitrectomy procedure,the illumination beam 354 may be generally ovoid in shape and centeredat the central illumination point 356, as shown in FIG. 5B. As shown inFIG. 5A, the illumination beam 354 may span an angle A1 and may have aportion that is tangential to the outer surface of the elongate tubularmember 342. In some implementations of the probe 300, the face 352 maybe angled such that no portion of the illumination beam 354 contacts theouter surface of the elongate tubular member 342 at all. For example,FIG. 5C provides a detailed view of the distal end of the optical fiber332 and the face 352 thereof. The face 352 may be a beveled face thatforms an angle A2, which may range from about 20° to about 50°. In someimplementations, the angle A2 is about 35°. Other angles arecontemplated in other implementations.

To protect the face 352 at the distal end of the optical fiber 332, thedistal end thereof may be offset from the distal edge 349 of the sheath340 by a distance D2, as shown in FIG. 5A. Implementations of the probe300 may include a distance D2 ranging from about 10 μm (micrometers) toabout 50 μm. In some implementations, the distance D2 may be about 25μm. This distance D2 may provide sufficient protection of the opticalfiber 332 and the face 352 and may also provide a limit to the angle A1of the illumination beam 354 to control the light and better enable thesurgeon to visualize tissue material proximate the distal tip 322,thereby aiding a surgeon in removing vitreous via the port 346. As shownin FIG. 5A, a central illumination point 356 may be angled away from thesurface of the outer tubular member 342 to avoid glare being reflectedoff the exterior surface. In some implementations, some rays of theillumination beam may be incident upon the exterior of the outer tubularmember 342.

The gap between the outer surface of the elongate tubular member 342 andthe inner surface of the sheath 340 further includes a fill material 358that covers a portion of the optical fiber 332. The fill material 358may be an adhesive material that serves to secure the optical fiber 332to the elongate tubular member 342 and/or the sheath 340. In someimplementations, the fill material 358 may be a portion of the sealantmaterial injected through the opening 348 in the sheath 340 as shown inFIG. 4B.

Referring now to FIGS. 6A and 6B, shown therein are implementations ofthe distal portion of the needle 320 of the probe 300. As shown in FIG.6A, a sealant material is visible in the opening 348 in the sheath 340.The sealant material may seal off any gaps that would otherwise bepresent between the elongate tubular member 342 and the sheath 340. FIG.6A also depicts a flat surface 360 formed on the elongate tubular member342. The flat surface 360 may provide a surface on which to secure theoptical fiber 332. Further, the flat surface 360 may be produced byremoving material from the elongate tubular member 342 such that thethickness of the wall of the elongate tubular member 342 is smaller atthe flat surface 360. This may facilitate inclusion of the optical fiber332 while mitigating any increase in the diameter of the needle 320.Accordingly, the thickness of the wall removed to provide the flatsurface 360 may correspond to the thickness of the optical fiber 332.Thus, in some exemplary implementations for a vitrectomy probe, about 20μm to about 150 μm of thickness may be removed. In some implementationsof the elongate tubular member 342, the lumen 347 extending therethroughmay be offset away from the flat surface 360 to provide for asubstantially uniform thickness of the wall at the flat surface 360 andof the wall of the elongate tubular member 342 opposite the flat surface360. The flat surface 360 may be a planar surface, in someimplementations.

FIG. 6B depicts an implementation of the needle 320 in which the outersurface of the elongate tubular member 342 is fully cylindrical, i.e.does not include the flat surface 360 shown in FIG. 6A. Theimplementation shown in FIG. 6B further depicts a patch of the fillmaterial 358 securing the optical fiber 332 in position under the sheath340. The depicted implementation also shows an elongate structurereferred to as a fiber guard member 364, which extends along a length ofthe elongate tubular member 342. The fiber guard member 364 may preventa compressive force applied by the sheath 340 from affecting theperformance of the optical fiber 332 and may ensure that the opticalfiber 332 remains aligned parallel to a central axis of the elongatetubular member 342, and may also ensure that the optical fiber 332remains free to displace axially along and independently of a proximalregion of the elongate tubular member 342, so as to reduce axial strainon the optical fiber 332 while permitting it to move independently intoand out of the slack chamber 330. In some implementations, the opticalfiber 332 may extend along the fiber guard member 364 for most of thelength of the optical fiber 332. The fiber guard member 364 may be anelongate structure, or series of aligned structures, such as a wire madeof metal or a polymeric material welded, adhered or otherwise joined tothe outer surface of the elongate tubular member 342. Otherimplementations of the fiber guard member 364 may include a glass fiberor a line of rigidized or cured polymeric material, such as an adhesive.The thickness of the fiber guard member 364 may be greater than adiameter of the optical fiber 332, which may range from about 20 μm toabout 150 μm, in various implementations. Accordingly, the thickness ofthe fiber guard member 364 may range from about 30 μm to about 200 μm,depending on the implementation. Naturally, some implementations of theneedle 320 may include both the flat surface 360 and the fiber guardmember 364. In some embodiments, a fiber guard member 364 that surroundsthe optical fiber 332 may be provided to protect the optical fiber 332.For example, the fiber guard member 364 may be provided by ametallization layer around a length of the optical fiber 332. Themetallization layer may provide structural rigidity to the metallizedportion of the optical fiber 332. Other rigid polymers may be usedrather than metal, in some embodiments. Embodiments of optical fiber 332having such a protective coating or surrounding structure may have adiameter less than 200 μm or less than 50 μm, for example.

Referring now to FIGS. 7A, 7B, and 7C, shown therein are aspects of anoptical fiber 700 which may be used in some implementations of theoptical fiber 332. The optical fiber 700 may include a transmissionassembly 702 and a distal assembly 704. The transmission assembly 702may comprise about 80% or 90% of the total length of the optical fiber700. For example, the transmission assembly 702 may be about 90 inchesin length, while the distal assembly 704 may be about 10 inches inlength. FIG. 7A depicts an optical fiber coupler 706 disposed at theproximal end of the optical fiber 700. The coupler 706 may secure theoptical fiber 700 to the console 102 of FIG. 1 or to the fiber subsystem120 contained therein. The coupler 706 may include an elongate portionthat may prevent kinking close to the proximal end of the optical fiber700. The optical fiber coupler 706 connects to a flexible outer member707, which may be the first conduit 106 as shown in FIG. 1 and describedherein. Accordingly, the flexible outer member 707 may contain andprotect an optical fiber core 708.

FIG. 7B shows the optical fiber core 708 as a compound optical fibercore having multiple components axially aligned and joined to transmitlight along the total length thereof. Some implementations of theoptical fiber core 708 may include a first fiber portion 710A and asecond fiber portion 710B. The fiber portions 710A and 710B may beformed from the same materials or from different materials. For example,the fiber portion 710A may be a silica or borosilicate fiber, while thefiber portion 710B may be a plastic fiber. In other implementations, thefiber portion 710A may be a plastic fiber, while the fiber portion 710Bis a glass fiber. The fiber portions 710A and 710B may be glued or fusedtogether.

As shown in FIG. 7C, the fiber portions 710A and 710B may be joined by atapered optical fiber section 712 that has a proximal end with a firstradius and a distal end with the second radius. The tapered opticalfiber section 712 may join fiber portions of different diameters. Insome implementations, the tapered optical fiber section 712 may beformed by heating the optical fiber core 708 and stretching the fiber.In some implementations, the tapered optical fiber section 712 may beabout 20 mm in length, and may join an optical fiber portion 710A havinga diameter of about 100 μm with an optical fiber portion 710B having adiameter of about 30 μm. These dimensions are exemplary only, and willvary depending on the implementation. In some implementations, a single,continuous optical fiber core extends the full length of the opticalfiber 700.

FIG. 8 shows an alternative sheath 340, according to aspects of thepresent disclosure. FIGS. 9A and 9B show the distal ends of exemplarysurgical instruments including the sheath 340 of FIG. 8, according toaspects of the present disclosure.

As described above, with an optical fiber 332 extending along a lengthof a tubular member 342 between the outer surface of the tubular member342 and an inner surface of a sheath 340, a space or gap may existbetween the tubular member 342 and the sheath 340. In someimplementations, the gap between the tubular member 342 and the sheath340 includes a fill material 358, such as an adhesive material, thatcovers a portion of the optical fiber 332 and serves to secure theoptical fiber 332 to the tubular member 342 and/or the sheath 340. Thefill material 358 may be injected through the opening 348 in the sheath340 as shown in FIG. 4B. The fill material 358 may completely or nearlycompletely seal the space or gap between the tubular member 342 and thesheath 340 in a circumferential direction around the tubular member 342,for example to prevent passive backflow of vitreous that could otherwiseoccur due to a higher pressure in the eye as compared to atmosphericpressure.

The fill material 358 may be located proximal to the distal end of theoptical fiber 332, so that the fill material 358 does not contaminate orotherwise obstruct the tip of the optical fiber 332. That is, while thefill material 358 may extend around the circumference of the tubularmember 342 within the sheath 340, in some implementations the fillmaterial 358 is limited in its extent in the longitudinal direction, andit does not extend to the distal end of the sheath 340. In such a case,distal to the fill material 358, a small unfilled space or gap remainsbetween the tubular member 342 and the sheath 340.

Air may be present in the space or gap between the tubular member 342and the sheath 340. When the microsurgical instrument or surgical probeis in use, that air may create an air bubble at the distal end of thesheath 340. For example, when the microsurgical instrument or surgicalprobe is inserted into the human body, such as into the posteriorchamber of the eye, the change in temperature from room temperature tobody temperature can cause the air within the space or gap between thetubular member 342 and sheath 340 to expand. Because the proximal end ofthe space or gap may be blocked, such as by the fill material 358 or byother structure, or because of the orientation of the instrument, theexpanding air may attempt to escape the space or gap between the tubularmember 342 and the sheath 340 by exiting the space or gap at the distalend of the sheath 340. Further, due to surface tension, the escaping airmay form an air bubble that remains in place at the distal end of thesheath 340. This, however, is in the location of the distal end of theoptical fiber 332, and if an air bubble is created by the exiting airand remains for any period of time at the distal end of the opticalfiber 332, the air bubble may interfere with the illumination of theoptical fiber 332. This may reduce the illumination and/or result in asuboptimal optical pattern, which may inhibit the visualization benefitsof the optical fiber 332.

In order to mitigate or inhibit the formation of air bubbles at the tipof the optical fiber 332, an opening, such as a slot, may be provided inthe sidewall of the sheath 340, adjacent to the air gap between thetubular member 342 and the sheath 340, at or near the distal end of thesheath 340, and proximal to the distal edge 349 of the sheath 340. Theopening may be located circumferentially away from the tip of theoptical fiber 332. Due to the nature of the air expansion in the areabetween the tubular member 342 and the sheath 340, the air bubble maytend to form at the opening rather than at the tip of the optical fiber332.

As an example, in FIG. 8, the sheath 340 has an opening 370 in the formof a slot extending proximally from the distal end of the sheath 340,proximal to the distal edge 349 of the sheath 340. The opening or slot370 is generally positioned circumferentially away from the tip of theoptical fiber 332. In the illustrated example (as shown in FIGS. 9A and9B), the opening or slot 370 is located 180-degrees away from theoptical fiber 332, but the opening or slot 370 may be positioned atother locations away from the optical fiber 332. The opening or slot 370has an edge 376 and a proximal end 378. Where the opening or slot 370meets the distal edge 349, the corners of the sidewall of the sheath 340may be rounded such that the sidewall has rounded edges 372, so as toavoid sharp corners, which could cause trauma or injury. Similarly, atthe proximal end 378 of the opening or slot 370, the sidewall of thesheath 340 may have rounded edges 374, again to avoid sharp corners.

FIGS. 9A and 9B show the distal ends of surgical instruments that aresimilar to the surgical instruments shown in FIGS. 6A and 6B, exceptthat in FIGS. 9A and 9B the sheath 340 has an opening or slot 370 asshown in FIG. 8. In such a surgical instrument, when air that is presentin the space or gap between the tubular member 342 and the sheath 340expands, any escaping air bubble(s) will tend to exit that space or gapat the opening or slot 370, away from the distal end of the opticalfiber 332. For example, due to the nature of the air expansion, anyescaping air bubble(s) will tend to exit that space or gap at theproximal end 378 of the opening or slot 370, or otherwise along the edge376 of the opening or slot 370, away from the distal end of the opticalfiber 332. Thus, the opening or slot 370 directs the air bubble(s) awayfrom the distal end of the optical fiber 332, to mitigate the potentialfor, or to avoid, having an air bubble interfere with the illuminationfrom the optical fiber 332. In some embodiments, the portion of thetubular member 342 under the slot in the sidewall of the sheath 340(e.g., the portion of the tubular member adjacent to the air gap at ornear the distal end of the sheath 340 and proximal to the distal edge349 of the sheath 340) may be polished or coated with a low frictioncoating (or both polished and coated) to further facilitate directingthe air bubble(s) away from the distal end of the optical fiber 332.

FIG. 10 is a cross-sectional illustration of the distal end of anotherexemplary surgical instrument similar to that shown in FIG. 5A,according to aspects of the present disclosure. FIGS. 11A-11E illustratea method of manufacturing the exemplary surgical instrument illustratedin FIG. 10.

As shown in FIG. 11A, an optical fiber 332A is placed on a positioningmember 400 used for manufacturing. The positioning member 400 may be,for example, a suitable pin, rod, or tube, which may be cylindrical orany other suitable shape. For example, the positioning member 400 mayhave the same outer diameter as the tubular member 342 to be assembledas part of the instrument. The positioning member 400 has a longitudinalaxis 402 as shown in FIG. 11A.

In some examples, the positioning member 400 may be made of or comprisea material or coating to prevent adhesion between the positioning member400 and the optical fiber 332A. For example, the positioning member 400may be made of or include a coating of polytetrafluoroethylene.

In other examples, the positioning member 400 may be made of or comprisea material or coating that melts at a lower temperature than the sheathmember 340A and optical fiber 332A, for purposes described furtherbelow. For example, the positioning member 400 may be made of or includea coating of wax.

Once the optical fiber 332A is placed on the positioning member 400, theoptical fiber 332A may be secured to the positioning member 400 in anysuitable manner. For example, a suitable adhesive may be used to securethe optical fiber 332A to the positioning member 400.

At the time of placing the optical fiber 332A on the positioning member400 and optionally securing it thereto, it may also be desirable toplace one or more fiber guard member(s) 364 as described above on thepositioning member 400 and optionally to secure such fiber guardmember(s) 364 to the positioning member 400 and/or optical fiber 332A.As described above, the fiber guard member(s) 364 can help maintain agap between the sheath 340A and the optical fiber 332A and can helpprotect the optical fiber 332A.

As shown in FIG. 11B, after the optical fiber 332A is placed on thepositioning member 400, and optionally secured to the positioning member400, a sheath member 340A may be placed around the optical fiber 332Aand positioning member 400. The sheath member 340A may be secured to theoptical fiber 332A to form a sheath member and optical fiber assembly.For example, the sheath member 340A may be secured to the optical fiber332A by a suitable adhesive 358. The sheath member 340A may also besecured to any fiber guard member(s) 364, if any is used. In order tomaintain the position of the optical fiber 332A, the adhesive 358 mayextend close to or beyond an angled plane at which material is to beremoved, as described in connection with FIG. 11C.

As shown in FIG. 11C, after the sheath member 340A is secured to theoptical fiber 332A, material is removed at an angle from a distal end ofthe sheath member 340A and optical fiber 332A such that an end surfaceof the sheath member and optical fiber assembly is angled at anon-perpendicular angle with respect to the longitudinal axis 402 of thepositioning member 400. The angled end surface of the sheath member andoptical fiber assembly comprises the angled end surface 341 of thesheath member 340 and the angled face 352 of the optical fiber 332. Todistinguish the sheath and optical fiber before and after removingmaterial, the sheath and optical fiber prior to this material removalare designated by the reference numerals 340A, 332A, respectively, andthe sheath and optical fiber after this material removal are designatedby the reference numerals 340, 332, respectively.

As shown in FIGS. 11B-11C, removing material from a distal end of thesheath member and optical fiber assembly may include removing materialfrom a distal end of the positioning member 400 such that an end surface404 of the positioning member 400 is angled with respect to thelongitudinal axis 402 of the positioning member 400 at the samenon-perpendicular angle as the angled end surface 341 of the sheathmember 340 and the angled face 352 of the optical fiber 332. Inalternative embodiments, the positioning member 400 as initiallyprovided may have an end surface that is coincident with the finaldesired angled end surface of the sheath member and optical fiberassembly or an end surface that does not extend past the final desiredangled end surface of the sheath member and optical fiber assembly, suchthat no material needs to be removed from the positioning member 400.Removing material from a distal end of the sheath member and opticalfiber assembly may also include removing some of the adhesive material358.

Removing material from a distal end of the sheath member and opticalfiber assembly may comprise angle polishing the sheath member andoptical fiber assembly with a suitable polishing tool. Other methods ofmaterial removal are possible, such as other forms of polishing orcutting.

As shown in FIG. 11D, after material removal is performed, creatingangled end surface 341 of the sheath member 340 and angled face 352 ofthe optical fiber 332, the positioning member 400 is removed from withinthe sheath member 340, with the sheath member 340 remaining secured tothe optical fiber 332. The removal of the positioning member 400 may beaccomplished in various ways.

For example, in methods in which the positioning member 400 is made ofor comprises a material or coating to prevent adhesion between thepositioning member 400 and the optical fiber 332, e.g.,polytetrafluoroethylene, the positioning member 400 may be removed bysliding it out of the sheath member 340. The adhesives used in theprocess create a firmer bond between the sheath member 340 and opticalfiber 332 than with such a non-stick positioning member 400, such thatthe positioning member 400 may be removed without disturbing the secureconnection between the sheath member 340 and the optical fiber 332.

In other examples, in methods in which the positioning member 400 ismade of or comprises a meltable material or coating that melts at alower temperature than the sheath member 340 and optical fiber 332,e.g., wax, removing the positioning member 400 from within the sheathmember 340 may comprise heating the positioning member 400 to melt themeltable material. This may melt the entire positioning member 400 orjust an outer portion or coating from it, sufficient to reduce its sizeto facilitate removal of the positioning member 400 from the sheathmember 340. Any remaining wax can be cleaned from the interior of thesheath member 340.

As shown in FIG. 11E, after removal of the positioning member 400, thesheath member 340 and optical fiber 332 are ready to be assembled withother components of the microsurgical instrument. As shown in FIG. 11E,the sheath member 340 with the optical fiber 332 secured thereto isplaced around the distally projecting tubular member 342. By maneuveringthe sheath member 340 rotationally and longitudinally with respect tothe tubular member 342, the optical fiber 332 can be aligned into thedesired position with respect to the port 346 of the tubular member 342.Once the desired alignment is achieved, the sheath member 340 may besecured to the tubular member 342, for example by using adhesives asdescribed above. For example, one or more openings 348 may extendthrough a sidewall of the sheath member 340, the opening(s) 348providing access to a volume defined by and between an inner wall of thesheath member 340 and the outer surface of the tubular member 342.Adhesive may be introduced through the opening(s) 348, wherein, oncecured, the cured adhesive at least partially fills the volume defined byand between the inner wall of the sheath member 340 and the outersurface of the tubular member 342 to provide a seal therebetween.

FIG. 10 shows further detail of FIG. 11E. An illuminated microsurgicalinstrument in accordance with FIG. 10 may be similar in all respects tothe illuminated microsurgical instrument in accordance with FIG. 5Adescribed above, except that the sheath member 340 and optical fiber 332have been manufactured together as described above, resulting in thegeometry shown in FIG. 10. Thus, the distal end 380 of the sheath member340 comprises an angled end surface 341 that lies in a plane at anon-perpendicular angle with respect to the longitudinal axis 362 of thetubular member 342, and the distal tip 350 of the optical fiber 332comprises an angled face 352 that lies in substantially the same planeas the angled end surface 341 of the sheath member 340. The assembly ofFIG. 10 may be integrated into a completed instrument system asdescribed above, for example in connection with FIGS. 1-4.

By the process described in connection with FIGS. 11A-11E, the opticalfiber 332 is fixed in position at least in part relative to the sheathmember 340. The angled face 352 of the distal tip 350 of the opticalfiber 332 is angled toward the outer surface of the tubular member 342.The angled face 352 of the distal tip 350 of the optical fiber 332causes a field of illumination to be directed substantially away fromthe outer surface of the tubular member 342. The angled face 352 of thedistal tip 350 of the optical fiber 332 may form an angle with respectto the outer surface of the tubular member 340 at any suitable angle,for example an angle ranging from about 20 degrees to about 60 degrees,or an angle ranging from about 30 degrees to about 40 degrees, or anyother suitable angle.

A distal edge 349 of the sheath member 340 is disposed at a locationcloser to the distal tip 322 of the tubular member 342 than is theoptical fiber 332, such that the optical fiber 332 is recessed from thedistal edge 349 of the sheath member 340, by the distance D2. Asdescribed above, the distance D2 may range, for example, from about 10μm (micrometers) to about 50 μm, but other distances are possible. Thisdistance D2 may provide sufficient protection of the optical fiber 332and the face 352 and may also provide a limit to the angle A1 of theillumination beam 354 to control the light and better enable the surgeonto visualize tissue material proximate the distal tip 322, therebyaiding a surgeon in removing vitreous via the port 346. The light at theangled face 352 may create a bright spot that could impair visibilityduring the procedure; thus, covering the angled face 352 with the sheathmember 340 helps block the bright spot in order to avoid having thebright spot impair visibility. In addition, having the angled face 352close to the distal edge 349 of the sheath member 340 helps avoidexcessive reflection of light from the internal surface of the sheathmember 340, which could occur if the distance D2 is too large in aparticular implementation.

In one example implementation, dimensions may be as follows. The opticalfiber 332 may have a diameter of about 20 μm to about 40 μm, or moreparticularly a diameter of 30 μm, although other sizes may be used. Thetubular member may be, for example, 27 gauge, having an outer diameterof about 400 μm, although larger and smaller sizes may be used. Thesheath member is sized to have an inner diameter large enough toaccommodate the tubular member and the optical fiber, with possibleclearance, for example to accommodate one or more fiber guards and/oradhesive, as described above. The sheath member may have a wallthickness of about 20 μm to about 25 μm, although other sizes may beused. These dimensions are only to give a possible example, asdimensions may be varied within the scope of the disclosure.

Although not illustrated in FIG. 10, in accordance with the variationsdescribed above with respect to FIGS. 8, 9A, and 9B, the sheath member340 in FIG. 10 may further comprise an opening 370 in a sidewall of thesheath member 340, the opening 370 being located adjacent to an air gapbetween the tubular member 342 and the sheath member 340, proximal to adistal edge 349 of the sheath member 340, and circumferentially awayfrom the distal tip 350 of the optical fiber 332. The opening 370 isadapted to direct air exiting the air gap away from the optical fiber332. The opening 370 may be in the form of a slot extending proximallyfrom the distal edge 349 of the sheath member 340.

The procedure as described above in connection with FIGS. 11A-11Eenables a simplified method for assembling the instrument and aligningthe fiber in the desired position. By assembling the optical fibertogether with the sheath member and undertaking angle polishing of thesecomponents while assembled together, the distance D2 of the angled facefrom the distal edge of the sheath member is automatically achieved.Also, with the optical fiber affixed to the sheath member, accurateclocking of the optical fiber relative to the port of the tubular memberis simplified, because it can be accomplished by maneuvering the sheathmember, which is larger, less fragile, and easier to handle than theoptical fiber. Thus, the method of manufacture helps accurately controlthe position of the fiber relative to the sheath member and relative tothe tubular member, in order to minimize glare and to achieve thedesired illumination.

Moreover, the optical fiber is fragile, difficult to handle, andsusceptible to damage. By assembling the fiber with the sheath memberbefore angle polishing, handling is facilitated and the potential fordamage is reduced.

In addition, because the adhesive can be applied before the angled faceis formed, the risk of adhesive contaminating the angle-polished fibertip can be mitigated. Adhesive contamination of the fiber tip can damagethe fiber or adversely influence the illumination pattern and thevitreous visualization. The method as described above helps keep thefiber tip clean. The method as described above also helps mitigate therisk of the fiber positioning changing relative to the sheath memberafter environmental conditioning.

The above method improves alignment and illumination, reduces thepotential for damage, and saves time and cost of manufacture. Theprocess can be automated to further reduce manufacturing cost.

As noted herein, some of the more specific implementations are describedwith respect to a vitrectomy probe in which an optical fiber providesfor illumination of the vitreous at the distal tip of the vitrectomyprobe. It should be noted that the described optical fiber may providefor other functions in other implementations. For example, the opticalfiber included in implementations of the surgical instrument 110 mayprovide for transmission of laser light to provide a photocoagulationlaser at a distal tip of the surgical instrument. Additionally, thesurgical instrument 110 may be a non-surgical medical instrument inother implementations. For example, additional implementations mayutilize the optical fiber in the performance of optical coherencetomography (OCT) imaging, rather than or in addition to any surgicalfunctions performed by implementations of the medical instrument.Accordingly, such surgical instruments are included within the scope ofthe present disclosure.

Persons of ordinary skill in the art will appreciate that theimplementations encompassed by the present disclosure are not limited tothe particular exemplary implementations described above. In thatregard, although illustrative implementations have been shown anddescribed, a wide range of modification, change, and substitution iscontemplated in the foregoing disclosure. It is understood that suchvariations may be made to the foregoing without departing from the scopeof the present disclosure. Accordingly, it is appropriate that theappended claims be construed broadly and in a manner consistent with thepresent disclosure.

What is claimed is:
 1. A method of manufacturing an illuminatedmicrosurgical instrument comprising: placing an optical fiber on apositioning member; placing a sheath member around the optical fiber andpositioning member and securing the sheath member to the optical fiberto form a sheath member and optical fiber assembly; removing materialfrom a distal end of the sheath member and optical fiber assembly suchthat an end surface of the sheath member and optical fiber assembly isangled at a non-perpendicular angle with respect to a longitudinal axisof the positioning member; removing the positioning member from withinthe sheath member, with the sheath member remaining secured to theoptical fiber; and placing the sheath member with the optical fibersecured thereto around a distally projecting tubular member.
 2. Themethod of manufacturing of claim 1, wherein the positioning membercomprises a material to prevent adhesion between the positioning memberand the optical fiber.
 3. The method of manufacturing of claim 2,wherein the material to prevent adhesion comprisespolytetrafluoroethylene.
 4. The method of manufacturing of claim 1,further comprising securing the optical fiber to the positioning memberprior to placing the sheath member around the optical fiber andpositioning member.
 5. The method of manufacturing of claim 1, whereinremoving material from a distal end of the sheath member and opticalfiber assembly comprises angle polishing the sheath member and opticalfiber assembly.
 6. The method of manufacturing of claim 1, whereinremoving material from a distal end of the sheath member and opticalfiber assembly includes removing material from a distal end of thepositioning member such that an end surface of the positioning member isangled with respect to a longitudinal axis of the positioning member atthe same non-perpendicular angle as the sheath member and optical fiberassembly.
 7. The method of manufacturing of claim 1, further comprising,after placing the sheath member with the optical fiber secured theretoaround a distally projecting tubular member, aligning the optical fiberwith respect to a port of the tubular member, and securing the sheathmember to the tubular member.
 8. The method of manufacturing of claim 1,wherein when the sheath member is secured to the tubular member, anangled face of the optical fiber is angled toward an outer surface ofthe tubular member.
 9. A method of manufacturing an illuminatedmicrosurgical instrument comprising: placing an optical fiber on apositioning member, wherein the positioning member comprises a meltablematerial that melts at a lower temperature than the sheath member andoptical fiber; placing a sheath member around the optical fiber andpositioning member and securing the sheath member to the optical fiberto form a sheath member and optical fiber assembly; removing materialfrom a distal end of the sheath member and optical fiber assembly suchthat an end surface of the sheath member and optical fiber assembly isangled at a non-perpendicular angle with respect to a longitudinal axisof the positioning member; removing the positioning member from withinthe sheath member, with the sheath member remaining secured to theoptical fiber, wherein removing the positioning member from within thesheath member comprises heating the positioning member to melt themeltable material; and placing the sheath member with the optical fibersecured thereto around a distally projecting tubular member.
 10. Themethod of manufacturing of claim 9, wherein the positioning membercomprises a material to prevent adhesion between the positioning memberand the optical fiber.
 11. The method of manufacturing of claim 10,wherein the material to prevent adhesion comprisespolytetrafluoroethylene.
 12. The method of manufacturing of claim 10,the meltable material comprises a wax.
 13. The method of manufacturingof claim 9, further comprising securing the optical fiber to thepositioning member prior to placing the sheath member around the opticalfiber and positioning member.
 14. The method of manufacturing of claim9, wherein removing material from a distal end of the sheath member andoptical fiber assembly comprises angle polishing the sheath member andoptical fiber assembly.
 15. The method of manufacturing of claim 9,wherein removing material from a distal end of the sheath member andoptical fiber assembly includes removing material from a distal end ofthe positioning member such that an end surface of the positioningmember is angled with respect to a longitudinal axis of the positioningmember at the same non-perpendicular angle as the sheath member andoptical fiber assembly.
 16. The method of manufacturing of claim 9,further comprising, after placing the sheath member with the opticalfiber secured thereto around a distally projecting tubular member,aligning the optical fiber with respect to a port of the tubular member,and securing the sheath member to the tubular member.
 17. The method ofmanufacturing of claim 9, wherein when the sheath member is secured tothe tubular member, an angled face of the optical fiber is angled towardan outer surface of the tubular member.